Dynamic modeling and experimental validation of infant-stroller vibration during road travel

This study presents the development and validation of a vibration model for an infant-stroller system. A theoretical framework was constructed to capture the dynamic interactions between the stroller structure and an infant model, in which joints were represented using spring-damper elements. Model validation was performed by comparing frequency response characteristics obtained from numerical simulations under sinusoidal excitation (5 mm amplitude, 0.1-10 Hz) with those measured on a random uneven road surface, as well as by comparing transient responses to a single-wavelength, inverted cosine-shaped bump (12 mm in height and 60 mm in width). Simulation results showed general agreement with experimental data, confirming the model’s fidelity. A parametric case study was conducted to investigate the effect of stroller center of gravity (CoG) on infant vibration exposure. Forward CoG shifts increased vertical accelerations of the seat, head, and torso, particularly during bump traversal, due to enhanced pitch motion. Conversely, placing the CoG near the infant’s seating position mitigated anterior-posterior vibration amplification. These findings suggest that the proposed model enables predictive analysis of how stroller configuration affects infant dynamic response. The framework may serve as a practical tool for optimizing stroller design parameters to improve comfort and safety. Future work will incorporate seat-contact effects, age-related anthropometric variation, and optimization-based parameter identification.